Rebuilt my party barge now have motor problems

[Keepseln]

Hi everyone,

I?m new to the forum and happy I found it, after reading a bunch of posts, I?m sure you?ll be able to help.

A little about Lenny (that?s the boats name by the way), it?s a 1988 suntracker party barge with a 90hp mariner outboard. I?ve owned this boat for a few years and it?s been a blast. To make a long story short, we decided to rebuild him from the ground up. Here is a link to his myspace page, were you can see pics of the rebuild.

www.myspace.com/lennythepartybarge

Ok, here?s were I hope someone can help, the motor. It?s been a bear to start this whole season, which I have attributed to being a carb problem with flooding. But about 5 trips ago the tach stopped working. I checked with a volt meter at the tach (the grey wire) and had varying readings with the throttle. So I chalked it up to the new tach might be bad. Then Sunday I had the whole family out and didn?t make it out of the slip. No spark on all 3 cylinders, so after an hour of trying to diagnose the problem (with almost no tools) we packed it in. Here?s the ?KICKER,? I went back Monday with all my tools and the boat fired right up, I mean like there had never been a problem, and ran all day.

Given the story I?ve told, are there any guesses as to where to start? I?d really appreciate any advice you guys might have.

Thanks

 

[The_Kid]

Re: Rebuilt my party barge now have motor problems

I've got a 115 Mariner that did the same thing to me. Died while I was on the lake and wouldn't restart. I was close enough to use the trolling moter to get to the dock. Next morning it it fired right up. Turns out the lanyard to the kill switch had pulled down just enough to kill the motor without triping the switch completly.

Of course I didn't find the problem until it stranded me in the middle of the lake the second time.

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

It's hard to keep a straight face when you reach over the gunwale of a boat that won't start and flip the kill switch for the poor fellow that has used most of his battery, and much of his vocabulary by then.

Happens all the time.

John

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

Back to the thread,

When there's an indication of trouble, that's the time to investigate and find it. If you put it off, another trouble may compound the original one, or the trouble may escalate into serious damage.
When it's hard to start, it's time to check the plugs, maybe compression, and fix whatever else is obvious, like flooding carbs.
When the tach dies, it usually, though not always, indicates trouble with the charging system. A weak battery will not only let you down, but is very hard on the $100 starter motor.
A 4 cycle engine with a weak fuel pump quits running, or runs poorly. A 2 cycle engine with a weak fuel pump generally eats pistons and spits the pieces out the exhaust port. It pays to keep on top of things.

It looks like yer into self service. Get a factory maintenance manual from your local mercury dealer, ask questions, and put it in shape.

hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

Thanks for looking in on my thread ? I consider myself a decent mechanic and have ordered the manual for this motor. (thanks iboats)

Some details ? 2 stroke motor that does not have a dead man switch ? I inspected the wiring from the motor to the helm and it?s intact.
On the Sunday I mentioned, the mechanic at the marina suggested I check a few things:
Motor serial #b175157
Neutral safety switch - Check
Dead man ? N/A
Black wire/yellow tracer ? when I disconnected the Black wire with the yellow tracer (at the switch box) there was no effect.
It was still disconnected on Monday when the boat started right up, when I turned the key off and the motor didn?t stop I realized it was still disconnected. I tried to reconnect it with the motor running and got shocked. Ouch!
Our thoughts were stator, because we lost all 3 cylinders, and then it fired right up the next day.

Here are a couple of questions:
What kind of voltage should I see from the sending wire of the Tach?
Could the ignition key/cylinder be going bad? (I read a post that had 12v in the run position but not at the start position.)

Thanks again
PS I attached a couple of pic so you can see the extent of the rebuild

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

If the key switch or dead man switch were bad, it would have started with the kill (black/yellow) wire disconnected.

You have an intermittent something, but don't know what. It could be stator low speed, or switchbox. Best bet would be to have a DVA in hand next time it fails, and check the charge coil readings on the stator at that time. If it's good, switchbox is bad. If it's bad, stator's bad.

I'd go through all the connections in the ignition, including each ground strap, and clean and tighten them. The problem might just go away.

The tach runs off a distorted half-wave pulse from one side of the bridge rectifier, or rectifier input stage of a voltage regulator. When the charging circuit fails, the tach also fails. The tach also needs 12 v and ground from the helm.

hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

I?m going back out Friday to work on it I?ll defiantly go through the connections on the motor.

You said ?When the charging circuit fails, the tach also fails.? How do I check the charging circuit, and would that identify a problem with the stator?

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

Check the battery voltage. If you have a dash mounted voltmeter, that's good enough. Should be 12.xx before start, up to 14 or more when running. Battery shouldn't go dead in use.

If that doesn't check out, go to the diode check thread in the FAQ's.

hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

Hey John,

I can tell you now that the volt meter has never read anywhere near 14v. If I run all day the voltage drops to right about 12, I've seen it as low as 11.7v, depending on the power in the batteries when we start the day.

-JB

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

Go here:

http://forums.iboats.com/showthread.php?t=190638

John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

You know it's funny, after your last post I went searching and found that exact thread. Printed it and ready for Fridays adventure. I'll take a minute and resize some pics. I'm very proud of the way the overall boat turned out. It's our intention to buy a new motor next year, but if I can get the bugs worked out, there might not be a need.

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

You know it's funny, after your last post I went searching and found that exact thread. Printed it and ready for Fridays adventure. I'll take a minute and resize some pics. I'm very proud of the way the overall boat turned out. It's our intention to buy a new motor next year, but if I can get the bugs worked out, there might not be a need.

Maintenance is the key. Abuse and ignore that engine, and it'll let you down shortly. Keep it up, especially in the lube and tune departments, and it'll probably outlive you.

hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

So it turns out I had a bad rectifier. Replaced it and got my tach working and low and behold a charging system. What I noticed though, is the voltage on the charging system seems to run way up there (16v) I know from my car audio experience that this is a good way to blow out electronics.
Does this motor have a voltage regulator?

Thanks for all the info. It?s been a big help.

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

So it turns out I had a bad rectifier. Replaced it and got my tach working and low and behold a charging system. What I noticed though, is the voltage on the charging system seems to run way up there (16v) I know from my car audio experience that this is a good way to blow out electronics.
Does this motor have a voltage regulator?

Thanks for all the info. It?s been a big help.

If it does, it's not very effective even when it's running. The Mercury low amperage systems rely on the battery holding the voltage down. 16 volts indicates a badly overdue battery.

Change it out for new, and all will be good. Again, the key is maintenance. The battery will lose water, and it needs to be kept up faithfully.

hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

So these motors rely on ?load? to keep the voltage regulated?
That would explain it.
A little test I did while on the water was to turn the battery switch too off, the voltage skyrocketed. So I turned everything on, the battery switch to ALL, turned the radio back on, everything. Then the voltage stayed around 13.5v. I just didn?t know if there might be a regulator that needs replacing.

The batteries aren?t very old (maybe 2 years) and because the charging system hasn?t been working since I?ve owned the boat, I?m pretty diligent about the maintenance on them.

You?ve really help give me some incite into this problem,
Thank you
-JB

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

If you have a regulator, it's probably on top of the motor, with one ground wire, and one red and one yellow going down to the rectifier.

Running with the battery disconnected, or bad battery connections, is about the quickest way to blow them.

I don't think Mercury even stocks them anymore. You can change out to one of the five wire or 6 wire regulators. It takes a little rigging and splicing, but if you use the rig a lot, it's probably worth the hassle. Hookup's pretty simple. Yellows go to stator, reds go to battery (solenoid) and grey goes to tach. Black, if there, is ground. It needs to be bolted to something that can carry away a little heat.

I went the whole way and changed my XR4 from 16 amp to 40 amp dual regulator, split system. Works great, flywheel cover won't fit, so link n sync requires finding the cover in the shop first.

hope it helps
John


hope it helps
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

Hey John,
I spoke to the mercury guys and they concur about having to splice in the new regulator, in fact they said to remove the rectifier all together. (guess I?m out that $50) Anyway, can you clarify how to connect the regulator to the existing? Is it as simple as making connections to the existing 2 yellows, 1 red, 1 grey and add the ground? Or, do I have to get to the stator to make the connection? Any help you may have is greatly appreciated.

-JB

 

[jimg984]

Re: Rebuilt my party barge now have motor problems

2 yellowswires,, 1 with grey wire (tach wire) connects to one of the yellow wires from the stator. 1 red wire to battery system. 1 wire to ground this is the connections for a rectiefer. voltage regulator would have the red wire connected thru it. could reduce the voltage thru a restat, instead of a voltage regulator if a person wanted to reduce the voltage. running lights would help reduce voltage also

 

[j_martin]

Re: Rebuilt my party barge now have motor problems

Hey John,
I spoke to the mercury guys and they concur about having to splice in the new regulator, in fact they said to remove the rectifier all together. (guess I?m out that $50) Anyway, can you clarify how to connect the regulator to the existing? Is it as simple as making connections to the existing 2 yellows, 1 red, 1 grey and add the ground? Or, do I have to get to the stator to make the connection? Any help you may have is greatly appreciated.

-JB

You got it right. it's that simple. The only other thing is the regulator needs to be bolted fairly tightly to a flat metal surface to get rid of a little heat.

However, your system will be running at full output most of the time just to keep up with a radio and running lights. I don't think It'd be worth the bother and expense to wire in a voltage regulator. If you totally fry your battery every other year, you'll put in 3 60 buck batteries in 6 years. Normally you would put in 2. So you save 10 bucks a year in battery life, if you're lucky.

If I were you, I'd run it like it is, maybe turn the radio up.

BTW 50 bucks is a bit steep for that $29 part.

hope it helps.
John

 

[Keepseln]

Re: Rebuilt my party barge now have motor problems

Thanks for the insite. I'm gonna take your advice, and turn the radio up. Adding draw to that system will be easy for me. The original stereo was 8 - 6x9's 2 - 10" subs and 3 amps, I cut it back because I thought I didn't have enough charging. Now that it's fixed it's time to scare some fishes.